Minus hydrogen ions have reducing power and are capable of, when taken into a body, effectively eliminating active oxygen (free radical) generated in the body. Hydrogen reacts with oxygen to generate water, and thus hydrogen has been attracting attention also as a global environment-friendly, clean energy resource.
The present inventor proposed a method for manufacturing a magnetic ceramic ball having a strong reducing potency (Japanese Patent document JP-B-4,218,939, published Jun. 24, 2004 as JP2004-174480, entitled “Method for Manufacturing Magnetic Ceramic Ball having Strong Reducing Characteristic”), and placing the ceramic ball in water, thereby causing the ceramic ball to generate hydrogen bubbles from the north pole thereof.